Well given that Mako cheated on Asami and Korra betrayed her friend (Asami), it would be reasonable to expect Asami to feel angry, and for their to be some fall out from that. But there wasn't.
Most of Book 2, Korra was off on her own. Bolin and Mako had split ways over their careers. In Book 3 the team got back together, but again, Korra ended up being off on her own for most of it.
Korra then fucks off for 3 years by herself. Doesn't bother to contact Bolin or Mako. Only Asami. She comes back, and she barely sees Mako and Bolin.
So you tell me. Why would they be friends? Why are they a team? Looking at their overall friendship and time as a team, they barely spent any time together. And there is a lot of personal issues that should have impacted their time together.
Asami pretty much spent zero time with Mako and Bolin in Book 4. And by the very end, Asami is with Korra off on their own. We never see the group together reflecting on the journey they were on together.
Legit, they spent barely any time together. So I don't see why you think they should be friends or a team. The plot didn't support it.